The invention relates to an assembled driveshaft in the case of which individual drive elements, especially gears, are non-rotatably attached to a hollow shaft, with seat diameters being stepped in at least one direction. The invention additionally relates to a shaft produced in accordance with this process. Furthermore, the invention relates to a process for producing an assembled driveshaft and a device in the form of a pressurizing probe for carrying out the process.
Assembled driveshafts of the above type are known; in the case of these, hollow shafts are used for weight saving purposes. DE 34 25 600 refers to such a shaft which is expanded in a die so that a stepped shaft with different seat diameters for the driving elements is produced. The seat regions are designed in the shape of polygons on to which the driving elements are slid to ensure form-fitting engagement.
A further prior art process for producing such shafts includes reducing the diameter of the ends of an originally straight tube by elongating or hammering, thereby producing a similar hollow shaft containing stepped portions towards its ends. The seat portions for the driving elements being provided with teeth for attaching the driving elements in a form-fitting way, preferably by non-chip-producing forming operations. Furthermore, it is also known to produce a stepped hollow shaft with external teeth by internally expanding a tube in a die. The teeth required in the seat regions being produced directly during the course of the forming process. With this method, a stepped hollow shaft may be composed of several individual parts (DE 29 14 657 C2). The process described here requires an expensive die adapted to the individual workpiece, and because of the high forming rates involved, the amount of energy required is relatively high.